feat(commands): improve discovery and normalize parameters

internal/modules/command_presentation_test.go

@@ -0,0 +1,59 @@
+package modules
+
+import "testing"
+
+func TestCommandPresentation(t *testing.T) {
+	tests := []struct {
+		name       string
+		command    Command
+		invocation string
+		example    string
+		menu       string
+	}{
+		{
+			name: "parameters and explicit example",
+			command: Command{
+				Name:        "stock_buy",
+				Parameters:  "<quantity> <ticker>",
+				Description: "Buy VN stock at market price",
+				Example:     "/stock_buy 100 TCB",
+			},
+			invocation: "/stock_buy <quantity> <ticker>",
+			example:    "/stock_buy 100 TCB",
+			menu:       "<quantity> <ticker>. Buy VN stock at market price. Example: /stock_buy 100 TCB",
+		},
+		{
+			name:       "no parameters uses command as example",
+			command:    Command{Name: "ping", Description: "Health check!"},
+			invocation: "/ping",
+			example:    "/ping",
+			menu:       "Health check! Example: /ping",
+		},
+		{
+			name: "variadic parameters keep ellipsis",
+			command: Command{
+				Name:        "random",
+				Parameters:  "<options(comma-separated)>",
+				Description: "Pick one option",
+				Example:     "/random pizza, sushi",
+			},
+			invocation: "/random <options(comma-separated)>",
+			example:    "/random pizza, sushi",
+			menu:       "<options(comma-separated)>. Pick one option. Example: /random pizza, sushi",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := tc.command.Invocation(); got != tc.invocation {
+				t.Errorf("Invocation() = %q, want %q", got, tc.invocation)
+			}
+			if got := tc.command.ExampleInvocation(); got != tc.example {
+				t.Errorf("ExampleInvocation() = %q, want %q", got, tc.example)
+			}
+			if got := tc.command.TelegramMenuDescription(); got != tc.menu {
+				t.Errorf("TelegramMenuDescription() = %q, want %q", got, tc.menu)
+			}
+		})
+	}
+}